1. Technical Field
The present invention relates to a packet switching network, and more particularly to a method for monitoring traffic in a packet switched network.
2. Related Art
Typically, a packet switched network such as an asynchronous transfer mode (ATM) is a network for integrating data and multimedia traffic into one network. Non-real-time traffic such as data and non-real-time traffic having audio and video signals are different in a quality of service (QoS) requirement. That is, the real-time traffic is very sensitive to data transmission delay, whereas the non-real-time traffic is very sensitive to data loss.
Since several streams of traffic having different quality of service (QoS) requirements share one source by adopting a statistical multiplexing method in the packet switched network, a predetermined network resource should be assigned to a corresponding connection whenever a connection is set up in such a way that the packet switched network satisfies a required quality of service (QoS) of the connection. Network resources include bandwidth, space in buffers, etc. Network resources can be said to be temporarily deficient when congestion occurs.
To reserve a network resource, a traffic source negotiates with a packet switched network using traffic parameters such as a maximum cell transmission rate, an average cell transmission rate, and a maximum burst length, and others. While setting up the connection, the packet switched network determines whether quality of services (QoSs) of prior connections besides the connection are satisfied using a call admission control mechanism, thereby determining a new call admission on the basis of the result. If a new connection is set up by the call admission control mechanism, then a source has to transmit traffic in conformity with the negotiated traffic parameters. However, if the source transmits much more traffic than the negotiated parameters, quality of services (QoSs) of not only the source but also of other sources may be deteriorated, and network congestion may occur.
It would be desirable to reduce the occurrence of network congestion, and it would be desirable to enhance the fair and uniform use of network resources.